Current control circuits are often arranged between a current source and an electric circuit for absorbing electric current from the electric circuit or for delivering electric current to the electric circuit. Ideally, the current control circuits are operable to regulate current between the current source and the electric circuit, giving high dynamic response, low noise, and high energy efficient current control.
Currently, these current control circuits either utilize a linear type series-pass device or a switched-mode power supply for current control.
Linear type series pass devices can generally provide fast dynamic response, small output ripple current and low output noise, and they do not require output filters. However, series pass devices suffer from low energy efficiency and lower power density. In addition, series pass devices only allows for unidirectional power flow, which may not be ideal in bidirectional operations.
On the other hand, switched-mode power supplies are usually energy efficient with high power density, and the same circuit can be used as both a current source and a current sink as they allow for bidirectional operation. However, switched-mode power supplies provide slow dynamic response, large output ripple current and high switching noise. Large output filter is also often required.
It is an object of the invention to address this need or, more generally, to provide an improved current control apparatus for regulating electric current between a current source and an electric circuit.